One thing readers need to keep in mind is that as Intruder mentions the LED alternatives, there is an added bonus that got left out:

Because the LED technology draws so much less current to perform, you can have more lights running at once on the same circuit with less worry about popping a breaker. To me, this is a major selling point.

i read some of the replies and let me tell you that american dj have alot of fixtures from plug and play which have a 10 min cycle and inteligent lighthing wich dont have a duty cycle but i would recomend that maybe you shuould invest in some accu scan 250, i have 8 of them and let me tell you that i had them for about 4 years so far i have no problem with them and also the light out put is really strong(discharge lamp) and also there is a really good thing that i did with mine. i had my own costum gobos made from a metal shop where a friend used to work, i put my logo. im pretty sure you can order this ones from ADJ for any dmx ficture. i also have some moving heads (power spot 250) but this are kind of expensive , so just stay with my recommendation, this way you will have a really good light show while showing that the fixtures you have in your dj system are not cheap. thank you for reading

ohh i almost forget check the dj equipment prices from all over your area and web sites, or discount stores. you will find that they are different prices all over, i live in san francisco and my local dj equipment store had my lights (accu scan) for 700 but i got them from a store in new york for a lot cheaper(brand new) even with the shipping. I save a lot of money. before you buy anything research feedback , the ups and downs of it and also thge price. hope this was a lil more helpfull in you quest to obtain the best lights for your show and buck.